The present invention relates to a beverage brewing apparatus adapted to prepare a beverage solution by immersing coffee powder or another type of powder in hot water and brewing the essence of this powder, and more specifically to a beverage brewing apparatus suited for an automatic vending machine.
Beverage brewing apparatuses of this type are stated in U.S. Pat. Nos. 3,203,340 and 3,221,637. In any of these conventional beverage brewing apparatuses applied to automatic coffee vending machines, a coffee solution is prepared on the same principle as in the so-called dripolator for household use. Namely, a coffee solution is obtained by immersing coffee powder in hot water so that the essence of the coffee powder is extracted into the hot water. In the prior art beverage brewing apparatuses, moreover, a cupful of coffee solution is produced by one cycle of brew and poured into a cup to be served to a customer.
The aforementioned conventional beverage brewing apparatuses have some drawbacks as follows. First, it takes much time to brew a coffee solution by immersing coffee powder in hot water, that is, to brew a cupful of coffee. This implies that these apparatuses, if applied to an automatic vending machine, force a customer (user of the vending machine) to have to wait a long time for a cup of coffee after he or she puts coins into the vending machine. Thus, the vending machine cannot fulfill its most essential requirement, fast service.
Secondly, the conventional method of coffee percolation is low in brewing efficiency, since the coffee powder cannot be in good contact with hot water. In other words, a lot of hot water would be used without touching the coffee powder. Therefore, the production of a desired quantity of coffee solution by brewing requires an increased amount of coffee powder, raising the cost of a every cup.